I had occasion to re-read the first book in the This Corner of the Universe series recently, as it was selected as the monthly (June) indie read in a Goodreads group I follow to discover new books. About two-thirds through the book, it occurred to me I should probably cite the military reference to vampires used in the book. Here’s an example:

Fifteen seconds after Heskan’s caution, the call came. Time lag had worked against Anelace, allowing the first pair of missiles to cover over half the distance between them and come within 41ls before her crew was even aware of their launch. “Vampires!” cried Truesworth, using the archaic warning for incoming missiles. “They’re second-gen Interceptor-B types judging by the emissions and flight characteristics.” The stress in Truesworth’s voice was apparent.

It’s one of many multiservice tactical brevity codes, meant to convey critical information quickly. “Vampire” doesn’t designate the specific type of missile (e.g., it can be coming from an air, submarine or surface launch). It’s just a fast way to get everyone on the bridge (and beyond) to focus on an immediate threat.